PT  - JOURNAL ARTICLE
AU  - Emiliano Santarosa
AU  - Paulo Vitor Dutra de Souza
AU  - Jorge Ernesto de Araujo Mariath
AU  - Gil Vicente Lourosa
TI  - Physiological Interaction between Rootstock-Scion: Effects on Xylem Vessels in Cabernet Sauvignon and Merlot Grapevines
AID  - 10.5344/ajev.2015.15003
DP  - 2015 Sep 03
TA  - American Journal of Enology and Viticulture
PG  - ajev.2015.15003
4099  - http://www.ajevonline.org/content/early/2015/08/31/ajev.2015.15003.short
4100  - http://www.ajevonline.org/content/early/2015/08/31/ajev.2015.15003.full
AB  - The interaction between rootstock and scion can interfere with the vegetative and productive balance of grapevines. Vascular connections and the vascularization pattern are parameters that potentially are related to the observed phenotype in a specific rootstock-scion combination. However, little is known about the physiology of the rootstock-scion interaction and the anatomical variables associated with this process. The aim of this study was to evaluate the interaction between rootstock-scion on the vegetative growth in Vitis vinifera L., with emphasis on vascular system variables. We investigated the rootstock genotypes Paulsen 1103 (Vitis berlandieri Planch. × Vitis rupestris Scheele), Mgt. 101-14 (Vitis riparia Michx × V. rupestris), and SO4 (V. berlandieri × V. riparia) and the Cabernet Sauvignon and Merlot varieties. We evaluated vegetative growth variables and performed an image analysis of the vascular system by quantifying the xylem and vessels (diameter, total number, density, frequency) in different portions of scion stem. The rootstock-scion interaction caused differences in vegetative growth and was associated with differences in the vascular system. The vegetative growth of the combinations Cabernet Sauvignon on Paulsen 1103 and Merlot on SO4 was higher than that of both varieties on Mgt. 101-14. The rootstock-scion combinations that are more vigorous showed vessels with larger mean diameter, larger xylem area, and higher frequency of vessels larger than 50μm. The vines grafted on Mgt. 101-14 resulted in more frequency of vessels lower than 40μm. For all combinations, the vessels’ features were altered from the apex to base sections (stem morphology). The physiological interaction between rootstock-scion resulted in modifications of the vascular system in grapevines, altering the xylem vessels features according to the specific rootstock-scion combination.